"There is work first to be done," Hilary, answered grimly. "There's a certain weather machine in the laboratory I want to take a look at."

"Weather machine?" Grim echoed, puzzled.

"Yes. The Viceroy let something slip about it. For some reason it's very important to them that it continues to function. I'm curious."

A gasp from Joan. Surprised, the men turned to her.

"Of course," she said breathlessly. "Father had been working on it for the longest time. It was a machine to control weather. Something to do with broadcasting tremendously high voltages, ionizing the air and causing rain clouds to form or reversing the process and scattering clouds back into thin air. This was the Master Machine. All over the Earth, at spaced distances, were smaller replicas, substations, controlled from this one. He had great hopes of furnishing equable weather to all the Earth. It was just completed, when...." She trailed off...

There were about a dozen Mercutians in the long laboratory, and each had a sun-tube dangling from his belt, ready at hand. The laboratory was crowded with apparatus, but what had drawn Hilary's attention was a gigantic gleaming metallic sphere set up prominently in the center of the room. Protruding from it at all angles were great quartz tubes, through which a blue light pulsed and flamed. It was connected by huge cables to a spark-bathed dynamo. Other cables writhed through the translucent ceiling. The weather machine!